Contractible mold.



PATENTED JAN. 15, 1907. G. GEoRGENsoN @L J. E. HENNEN.l

CONTRAGTIBL'B MOLD. APPLIGATION' FILED sEPT.25.1ooe.

f 1s being formed of sheet metal and provided inscription.

To itil iuionc it may-concern.:

yinsrrED STATES PATENT, OEEIOE.

GEORGE GEORGENSONAND JOSEPH E. HENNEN, or FOND nume, l WISCONSIN. i 'f 'CONTRACTIBLE MOLD. j

' Be it known that we, 'GEoReE GEOEOEN- son and JOSEPH E. HEN'NEN, citizens of the LUnited States, and residents of Fond du Lac, in the county of Fond du Lac and State of Wisconsin, have invented an Improved Con-` tractible Mold, of which the following is a de- Our invention is an improved iiexible mold for use in the construction of arches, culverts, sewers, or the like in ,which'a temorary supportis required for the cement, rick, or stone employed in the construction. In carrying out our invention We employ what may be termed a cylinder, the same teriorly with means for expanding and contracting it.

The details of construction, arrangement, and combination of parts embodying our inventio'n are as hereinafter described, and illus,` trated in the accompanying drawings, in which-v 'Figure 1 is an end elevation of the mold. Fig. 2 is a transverse section ofthe saine.

Aindicates the shell of the mold, the same l" 'being formed of sheet metal combinin a due degree of elasticity and rigidity Where y it is adapted for suppcrtin an arch for the concrete or other materia and to be closed or contracted for reducing its diameter as required td' enable it to be Withdrawn when the 'arch has been completed. The shell is prof-- erably constructed in one piece for the sake of economy and uniform elasticity, although it is obvious it may be constructed in ieces or sections, whose edges shall be l' rmly united. It is made of any desired or practicable len th and is adjusted from time to time lengt wise according to the length of the arch or otherwork being done. In this linstance the ends or edges of the sheet metal overlap; but they might be separated by a narrow space. The slze or ldiameter of the mold Will of course be varied according to different kinds of woik. The contractmg and expanding lmechanism arranged within the shell A is composed of the following arts: A polygonal shaft B .is arranged centra ly or coincident with thc axis of. the shell A, and it 'is provided with a series of rigid radial arms C C C2 C3, which are in 'turn connected with the shell by links or connecting-bars D, D,

D, and D3. The outer ends of these links or Specification of Letters Patent. Application nea spmib 25, isos. serial No. 336.115.

i Patented J zam-15, 1907.

i bars are not attached directlyto the shell,

but to a series of lugs E, the same being con# structed in. such manner thatthey may be riveted to the shell and allow due movement of the several links or conneting-bars. `A handle F is mounted o'n the.\protruding end tithe shaft B for use in rotating the latter. I will be seen that the several \.arms C C', tc'., differ in length, the-armsy C being the shortest and the others increasing in length i rogressively. The links or connecting-bars D', &c., vary inversely inlength,t he bar D being the longest and thev others being madeprogressively shorter, corresponding to the increasing length of the arms C CI C2. The object of this construction is asl follows: When the ps rts-are in the'normal position, (shown by full lines,) the shell A closely a prOX-iniates a true' circle. It isl absolute necessary, however, that in contracting the shell it should not be thrown into elliptical .forni in cross-section, since itvmight in such case still be or remain in contact with the Work at two points in its circumference. l We i have found that in order to pervent this or,

in other Wordsin order that the shell when contracted should still closely approximate a true ncircle it is necessaryv thatthe several arms C C', &c., should vary progressively 'in length, as illustrated in the drawln s. -Thus it is necessary that the pivots Whic connect the several links or bars D D', &c., Withthe radial arms C C', &c., should not be located a uniform distance from the centerV of the shell, which is the poly onal shaft B, since otherwise the shell coul not be contracted in. a true or practically true circular form.

-In practice let it be supposed that the distance from the shaft B to the pivot-hole of thefirst arm C is one inch. Then the corresponding distance on the secondarm C would be two inches, on the third arm C2.

three inches, and on the fourth arm C3 four inches.` It is obvious that by adjustngthe handlever F in the direction ofthe arrow, Fi l -xiop the mechanism connected therewith wil 'be thrown into the positions 'indicated by dotted .l lines, and the shell will also assume the contracted form represented by dotted lines, the

By providing either? the ma o of, au., er. Y.

' ing the lever F. Such forpnyis'V r, nisitevori .,desired.,iii-somerlriidsA of'work, twill be f `form shaft and the connecti .the bars D D ,7&c., with holes, as indicated in Athat connect the arms and be shifted, and thus the shell may,`

seen that lin anyu case xor ,Whatever be the l lofflshell it is supported or braced inA teriorljr Wheneverv the i radial arms ..4 of the alinement,k as shwnl'by 'K What We claim is---v A c'ontractible A r` vfo'rniedfof ysheet metalI a central shaft having y n' in/,lengthfand aflikueseries yo izo.

a series of radial ari'nsdii'erin Yrogressivelyv 'connecting saidarms with. the shell and vary# l links ori-harsv are 1n v.

mad message Siren nks ori bfars l ing in length inversely as to the arms, silbstantially as described;

prising ailexible shell, a central shaft having a lever adapted for rotating it, and a series of rigid arms which' are fast on said shaft and y differ progressively lin length, 'a series of links .iorbars Apivoted to the arms and at their outer GEORGE, GORGNSQN. JOSEPHk E. HENNEN.

stantiallyas described.

' y -Witn`essesfor George Georgenso'n'zjvj.

l Witnesses orJoseph E. Hennen? 2. The im roved contractible mold com-I ends to the shell and viyii-,gpropressitgailyfin.l length bntjnverselyastothe said arms, sub- 3 

